Injection device

ABSTRACT

An injection device includes a housing having a proximal end and a distal end, the housing defining a distal opening, and a first opening in a side of the housing and between the proximal and distal ends; a propellant disposed inside the housing and spaced from the distal end; and a movable member disposed inside the housing and between the distal end and the propellant, wherein the propellant is in fluid communication with the movable member and the first opening.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.09/755,906, filed Jan. 5, 2001, now U.S. Pat. No. 6,616,627, issued Sep.9, 2003, which claims priority under 35 USC §119(e)(1) to U.S. patentapplication Ser. No. 60/174,876, filed on Jan. 7, 2000, the entirecontents of which are hereby incorporated by reference.

BACKGROUND

The invention relates to injection devices (e.g., injection devicesincluding a needleless syringe), as well as components that can be usedin injection devices.

Injection devices can be used for fluid injection into a body. Someinjection devices can include a needleless syringe.

SUMMARY

The invention provides one or more components (e.g., a gas generant unitand/or a housing unit) that can be used in an injection device (e.g., aninjection device including a needleless syringe), and injection devicescontaining one or more of these components.

The components can be removable, replaceable and/or adaptable to fitdifferent sized injection devices. The injection devices can bere-usable. The injection devices can be in any of a variety of shapesand sizes.

For embodiments in which the injection device includes a gas generantunit, the gas generant unit can be removed before or after use of theinjection device. Moreover, a gas generant unit that is removed from thesyringe can be replaced with a different gas generant unit, which maycontain the same or different gas generant compounds. Furthermore, a gasgenerant unit can be adaptable to fit different sized injection devices.Advantages associated with an injection device that is capable of usingsuch a gas generant can include re-usability, relatively low cost tomanufacture, relatively low cost to use, and/or enhanced flexibility inmaterials used as gas generant and/or injection fluid.

The injection device can include a housing that allows a fluid (e.g., agas, such as a product of the reaction of the gas generant) to travelbetween the interior of the injection device and the exterior of theinjection device without passing through the distal end of the injectiondevice (e.g., the exit port of a syringe, such as a needleless syringe,contained within the injection device). In certain embodiments, thisfeature can be provided, for example, by including the followingcomponents in the housing: a sliding piston, a sleeve (which can haveone or more venting mechanisms, such as one or more venting grooves,e.g., annular venting groove(s)), and one or more pressure reliefmechanisms (e.g., one or more pressure relief holes). In theseembodiments, the sliding piston can be designed to move along the sleeveso that, at one or more points along the path of motion of the slidingpiston, the pressure relief mechanism(s) of the sliding piston align(e.g., partially align or fully align) with the pressure reliefmechanism(s) in the sleeve. When this occurs, the fluid (e.g., reactantgas) can pass between the respective relief mechanism(s). The fluid(e.g., reactant gas) then exits the injection device via a passagewaythat does not include the distal end of the injection device (e.g., theexit port of a syringe, such as a needleless syringe, contained withinthe injection device).

In one aspect, the invention features an injection device, such as aneedleless injection device, having a housing having a proximal end anda distal end, the housing defining a distal opening, and a first openingin a side of the housing and between the proximal and distal ends; apropellant disposed inside the housing and spaced from the distal end;and a movable member disposed inside the housing and between the distalend and the propellant, wherein the propellant is in fluid communicationwith the movable member and the first opening.

Embodiments include one or more of the following features.

The propellant is capable of forming a gas capable of moving the movablemember in a distal direction and flowing through the first opening tothe exterior of the housing.

The movable member comprises a piston defining a cavity, and thepropellant is in fluid communication with the cavity. The movable memberfurther defines a second opening in fluid communication with the firstopening.

The device further includes a hollow sleeve configured to mate with thepiston, the sleeve defining a second cavity in fluid communication withthe propellant. The sleeve further defines a third opening alignablewith the second opening. The sleeve further defines a groove, and thethird opening is disposed in the groove.

The device further includes a button at the proximal end of the housing;a battery inside the housing and adjacent to the button; electricalleads in electrical communication with the battery; and a wire inelectrical communication with the electrical leads, the wire configuredto trigger the propellant.

The distal opening of the housing is configured to mate with a proximalend of a syringe. The syringe includes a plunger, and the movable memberis configured to move the plunger in a distal direction.

The propellant includes a chemical pyrotechnic material.

The housing is composed of a plurality of detachable housings.

In another aspect, the invention features an injection device, such as aneedleless injection device, having a housing having a proximal end anda distal end, the housing defining a distal opening, and a first openingin a side of the housing and between the proximal and distal ends; apropellant disposed inside the housing and spaced from the distal end; asleeve disposed inside the housing and between the distal end and thepropellant, the sleeve defining a second opening and a first cavity, thesecond opening and the first cavity in fluid communication with thepropellant; and a piston mateable with the sleeve and movable in adistal direction, the piston defining a third opening alignable with thesecond opening, wherein the propellant is in fluid communication withthe first opening when the second and third openings are aligned.

Embodiments include one or more of the following features.

The propellant is capable of forming a gas capable of flowing throughthe first cavity to move the piston, wherein the gas flows through thesecond and third openings when aligned, and through the first opening.The propellant includes a chemical pyrotechnic material.

The piston is coaxial with the sleeve and slidable over the sleeve toalign the second and third openings. The piston defines a plurality ofopenings alignable with the second opening.

The sleeve defines a groove, such as an annular groove, the secondopening disposed in the groove.

The distal opening of the housing is configured to mate with a syringehaving a plunger, and the piston is configured to move the plunger.

The device further includes a button at the proximal end of the housing;a battery inside the housing and adjacent to the button; electricalleads in electrical communication with the battery; and a wire inelectrical communication with the electrical leads, the wire configuredto trigger the propellant.

The housing further defines an elongate passageway between the firstopening and the third opening.

The device further includes a filter between the propellant and thefirst cavity.

The housing is composed of a plurality of detachable housings.

In another aspect, the invention features an apparatus that includes ahousing, a button connected to the housing, a battery adjacent thebutton and connected to the housing, electrical leads in electricalcommunication with the battery, and a wire in electrical communicationwith the electrical leads.

In another aspect, the invention features an apparatus that includes asleeve having a surface having at least one hole, a movable pistonhaving at least one hole and a surface adjacent the surface of thesleeve, and a first housing connected to the sleeve and the movablepiston.

In a further aspect, the invention features an injection deviceincluding first, second, third and fourth housings. The first housing isdemountably attached to the second housing. The second housing isdemountably attached to the third housing. The third housing isdemountably attached to the fourth housing. The first housing includes abutton and a battery adjacent the button. The second housing includes aninner housing, electrical contacts within the inner housing, a wirewithin the inner housing and in electrical communication with theelectrical contacts, and a gas generant within the inner housing. Thethird housing includes a syringe adaptor housing having an outer ventsleeve, a movable piston having an end and at least one relief hole, afixed sleeve having a groove with a hole (e.g., a pressure relief hole),the fixed sleeve being adjacent the movable piston, a drive pistonhaving at least one groove, the drive piston being adjacent the end ofthe movable piston and a sealing device within the groove of the drivepiston. The fourth housing includes a plunger having an end, a syringeadjacent the end of the plunger, and an elastomeric spring adjacent thesyringe.

Other features, objects, and advantages of the invention will beapparent from the description and drawings, and from the claims.

DESCRIPTION OF DRAWINGS

FIG. 1 is a cross-sectional view of an embodiment of an injectiondevice;

FIG. 2 is a partial cross-sectional view of an embodiment of a portionof an injection device; and

FIG. 3 is a partial cross-sectional view of an embodiment of a portionof an injection device.

DETAILED DESCRIPTION

The invention relates to injection devices (e.g., injection devicescontaining needleless syringes) and components that can be used in suchinjection devices. Advantages of the injection devices can include thatthey are relatively safe to use, relatively less painful to use, capableof delivering fluid in a predetermined and/or desirable manner, and/orreusable.

FIG. 1 shows a cross-sectional view of an embodiment of an injectiondevice 5. Device 5 includes housings 10, 20, and 30. Housing 10 isdemountably attached to housing 20 at section 25 by for example, screwthreads or a bayonet lock. Housing 20 is demountably attached to housing30 at section 26 by, for example, screw threads or a bayonet lock.Housing 30 is permanently attached to a bayonet interlock syringeadaptor 200 to provide a mechanism for fitting a syringe configuration.

Housing 10 includes a button 40, a battery 50, and an electricallyinsulative (e.g., non-metallic) cup 620 (FIG. 3).

Housing 20 encloses a housing 80 (e.g., a disposable housing) havingelectrical contacts 60, a wire 70 and a propellant 90, such as a gasgenerant (FIG. 2).

The syringe adaptor 200 has an outer vent sleeve 150, a sliding piston100 having pressure relief holes 130, sleeve 10 (e.g., a fixed sleeve)having a groove 120 (e.g., an annular groove), and a drive piston 170having grooves containing sealing devices 180 (e.g., o-rings) and asyringe interface 190 (e.g., a custom syringe interface) located at itsdistal end. The sliding piston 100 includes a proximal end toward theproximal end of the housing and a distal end toward the distal end ofthe housing. The sleeve 110 includes a proximal end toward the proximalend of the housing and a distal end toward the distal end of thehousing.

In some embodiments, the injection device 5 is assembled as follows.Sleeve 110 is permanently attached to housing 30, followed bypermanently attached outer vent sleeve 150 to the flange of sleeve 110.Then, elastomeric spring 210 is bonded to the end of housing 30, andsyringe adaptor 200 is subsequently permanently attached to housing 30.

Syringe adaptor 200 (e.g., an interlock adaptor) accepts a syringehousing 220 with its associated plunger 230.

FIG. 2 shows an exploded view of an embodiment of housing 80 includingelectrical contacts 60, wire 70, propellant 90, screen 240, filter 250and cap 260 with an exit hole 270.

FIG. 3 shows an exploded view of an embodiment of sleeve 110, annulargroove 120 having hole(s) 300, sliding piston 100 and vent holes 130.

During operation of injection device 5, button 40 (e.g., a moldedplastic button) is pressed, compressing a wave spring 610 which causesbattery 50 (e.g., a replaceable battery) to come into contact withelectrical contacts 60. This causes an electrical current to passthrough wire 70 (e.g., a metal wire such as nickel/chromium wire, and/ora wire having a diameter of from about 0.005 inch to about 0.010 inch,such as about 0.010 inch), thereby heating wire 70 (e.g., causing wire70 to become red hot in about one second). The heat generated by wire 70is sufficient to cause the reaction of chemical components contained inpropellant 90. Such chemical components can include a fuel and anoxidant. A nonlimiting, illustrative list of examples of chemicalcomponents that can be used in propellant 90 (e.g., a gas generant) aredisclosed in U.S. Pat. Nos. 4,103,684; 4,342,310; 4,447,225; 4,518,385;4,592,742; 4,623,332; 4,680,027; 4,722,728; 4,913,699; 5,024,656;5,049,125; 5,064,123; 5,190,523; 5,304,128; 5,312,335; 5,334,144;5,383,851; 5,399,163; 5,499,972; 5,501,666; 5,503,628; 5,520,639;5,569,189; 5,630,796; 5,704,911; 5,730,723; 5,840,061; 5,851,198;5,879,327; 5,899,879; 5,899,880; 5,911,703; and 5,993,412, each of whichis hereby incorporated by reference. Other chemical components aredescribed in commonly-assigned Application No. 60/250,573, filed Nov.30, 2000, and entitled “Injection Devices”, hereby incorporated byreference.

The gas formed by the reaction of the chemical components in propellant90 passes through screen 240 (e.g., metal screen, such as a stainlesssteel screen of, for example, about 50 to 200 mesh) and filter 250(e.g., a glass fiber filter). Screen 240 can cool the reactant gasand/or trap slag, and filter 250 can trap particulates (e.g., smallparticulates, such as those generated during the reaction).

After passing through filter 250, the reactant gases cause slidingpiston 100 to move along the surface of sleeve 110. As piston 100 movesalong the surface of sleeve 110, piston 100 urges drive piston 170 topush against plunger 230 which, in turn, pushes against fluid withinsyringe 220, thereby ejecting fluid from syringe 220 via outlet 310.

The movement of piston 100 along the surface of sleeve 110 also causesholes 130 to reach the annular groove 120. When this occurs, thereactant gas can pass through one or more holes 300 (i.e., one, two,three or four holes) in the annular groove 120 and one or more of holes130. The reactant gas that passes through holes 300 and hole(s) 130 canflow through relief channels 140, into space 160 (e.g., an open space,or a space containing a filter material, such as glass wool) and outdevice 5 via gas vent 7.

The number, size and location of holes 130 can vary to assist incontrolling the pressure of fluid exiting through distal end 310 ofinjection device 5. The location of holes 130 can be determined byinterfacing the end of the syringe to a pressure transducer that in turnis interfaced to a real time data acquisition system. One example is amodel PCI-731/6040E data acquisition board (commercially available fromNational Instruments of Austin, Tex.), which can be interfaced to acomputer (e.g., a personal computer) for real time pressure transducermeasurements. Changes in the pressure profile due to changes in theplacement, shape, and size of holes 130 can be monitored and optimizedaccordingly.

The use of annular groove 120 can obviate the need for a precisealignment of holes 130 because holes 130 are not required to be keyed tocontact groove 120.

Syringe 220 and plunger 230 can take on a variety of shapes and sizes.For example, syringe 220 and plunger 230 can be commercially availablecomponents (e.g., such as available from Bioject Medical, located inPortland, Oreg.; Injet Medical Products, Inc., located in Lake Forest,Ill.; and Avant Drug Delivery Systems, Inc., located in San Diego,Calif.).

The end of housing 30, syringe adaptor 200 and elastomeric spring 210form an interlock, which, in certain embodiments, can be designed toaccept the attachment of commercially available syringes and/or ampules.The interlock may be one of several types including a bayonet type.

In certain embodiments, housing 80 is replaceable. In these embodiments,after an injection housing 80 can be removed and replaced with adifferent housing, and device 5 can be re-used.

The invention is not limited by the above description, and the inventioncontemplates variations and modifications to this description. Forexample, in some embodiments, housings 10, 20, and 30 can benon-demountable.

In some embodiments, the invention provides for the delivery of amixture of two substances.

The first substance can be a dry substance, e.g., a lyophilized protein,nucleic acid, e.g., RNA or DNA, or polysaccharide. The first substancecan be a vaccine, or a drug. The first substance can be a peptide,polypeptide, or protein, e.g., an antibody, an enzyme, a hormone orgrowth factor. Preferred first substances include insulin. The firstsubstance can be: a blood protein, e.g., clotting factor VIII or a IX,complement factor or component; a hormone, e.g., insulin, growthhormone, thyroid hormone, a catecholamine, a gonadotrophin, PMSG, atrophic hormone, prolactin, oxytocin, dopamine and the like; a growthfactor, e.g., EGF, PDGF, NGF, IGF's and the like; a cytokine, e.g., an,interleukin, CSF, GMCSF, TNF, TGF-alpha, TGF-beta. and the 25 like; anenzyme, e.g., tissue plasminogen activator, streptokinase, cholesterolbiosynthetic or degradative, glycosolases, and the like; a bindingprotein, e.g., a steroid binding protein, a growth hormone or growthfactor binding protein and the like; an immune system protein, e.g., anantibody, SLA or MHC gene or gene product; an antigen, e.g., abacterial, parasitic, or viral, substance or generally allergens and thelike.

The second substance can be a liquid, e.g., a diluent or solute. Suchliquids can include buffers, inert fillers, pharmaceutically acceptablecarriers, or the like.

The subject can be a human or an animal, e.g., a laboratory animal, orpet, e.g., a dog or cat, or other animal, e.g., a bovine, a swine, agoat, or a horse. The first and second substance can be combined by thesubject, or by another person.

Other embodiments are in the claims.

1. An injection device for fluid injection into a body comprising: ahousing having a proximal end and a distal end, the housing having anopening proximate the distal end, the opening configured to deliver afluid; a fluid chamber disposed inside the housing and configured tocontain the fluid; a propellant chamber disposed inside the housing andspaced from the distal end of the housing; a sleeve having a proximalend and a distal end, the sleeve disposed inside the housing between thedistal end of the housing and the propellant chamber, the sleeve havinga first cavity in fluid communication with the propellant chamber, andhaving an opening between the proximal end of the sleeve and the distalend of the sleeve; and a piston mounted on the sleeve and having aproximal end and a distal end and having an opening between the proximalend of the piston and the distal end of the piston, the piston beingcoupled to the sleeve and having a second cavity, the piston beingmovable with respect to the sleeve from a first position to a secondposition, wherein, during use, a fluid is released from the propellantchamber causing the piston to slide over a surface of the sleeve fromthe first position to the second position, movement of the pistoncausing the fluid in the fluid chamber to be ejected through the housingopening, and wherein as the piston slides over the sleeve, the openingof the piston aligns with the opening of sleeve such that at least someof the fluid from the propellant chamber travels through the alignedopenings of the sleeve and piston.
 2. The injection device of claim 1,wherein the opening of the piston is configured to assist in controllingpressure of the fluid being ejected through the housing opening.
 3. Theinjection device of claim 1, wherein the sleeve further includes agroove, the opening of the sleeve disposed in the groove.
 4. Theinjection device of claim 3, wherein the groove is annular.
 5. Theinjection device of claim 1, wherein the opening of the piston includesa plurality of axially spaced openings that are each alignable with theopening of the sleeve.
 6. The injection device of claim 1, wherein thehousing is comprised of a plurality of housing components.
 7. Theinjection device of claim 1, wherein the fluid from the propellantchamber is a gas that urges the piston from the first position to thesecond position.
 8. The injection device of claim 1, wherein the secondcavity is in fluid communication with an exterior of the housing whenthe piston and sleeve openings are aligned.
 9. The injection device ofclaim 1, wherein the fluid from the propellant chamber is released froma propellant disposed within the propellant chamber.
 10. The injectiondevice of claim 9, further comprising: a button coupled to the housingproximate the proximal end of the housing; a battery disposed inside thehousing and adjacent to the button; electrical leads in electricalcommunication with the battery; and a wire in electrical communicationwith the electrical leads, the wire configured to trigger thepropellant.
 11. The injection device of claim 9, wherein the propellantincludes a chemical pyrotechnic material.
 12. The injection device ofclaim 1, wherein the device is a needleless injection device.
 13. Theinjection device of claim 1, further comprising: a filter disposedbetween the propellant chamber and the first cavity.
 14. The injectiondevice of claim 1, wherein the housing includes a vent, at least some ofthe fluid from the propellant chamber exiting through the vent aftertraveling through the openings of the sleeve and the piston.